Impact of hydrogen-rich gas mixture inhalation through nasal cannula during post-exercise recovery period on subsequent oxidative stress, muscle damage, and exercise performances in men
Shibayama Y et al. · Med Gas Res. 2020;10(4):155–162.
Study at a glance
Human
Healthy physically active young men able to perform high-intensity cycling
A hydrogen-rich H₂/O₂ gas mixture was inhaled through a nasal cannula for 60 minutes during recovery after strenuous treadmill running and squat jumps. · Generator outlet: 68.0% H₂ and 32.0% O₂. After dilution with room air during spontaneous breathing, the paper estimated inspired fractions of at most 4.08% H₂ and 21.57% O₂.
60-minute post-exercise inhalation in each condition, separated by more than one week
Compared with placebo, the H₂/O₂ mixture attenuated the rise in urinary 8-OHdG and the reduction in countermovement-jump height. Other measured performance, blood oxidative-stress and muscle-damage outcomes did not differ.
Very small male-only study. Because the intervention co-delivered O₂, the isolated effect of H₂ cannot be established. Helix Japan funded the study and supplied the gas generator.
What kind of evidence is this?
Human
Randomized double-blind placebo-controlled crossover repeated-measures study
Exercise and recovery
Inhaled H₂
Information not yet classified
Some editorial classification fields are still pending. The source-reported outcomes and result are shown below; Hydrogenology does not infer a positive or negative signal from prose automatically.
Methods
Healthy physically active young men able to perform high-intensity cycling
8 participants
60-minute post-exercise inhalation in each condition, separated by more than one week
A hydrogen-rich H₂/O₂ gas mixture was inhaled through a nasal cannula for 60 minutes during recovery after strenuous treadmill running and squat jumps.
H₂/O₂ gas mixture — H₂ and O₂ were co-delivered, not H₂ alone. It is an oxyhydrogen mixture, but not the exact 66.666% H₂ / 33.333% O₂ Brown’s-gas proportion.
Generator outlet: 68.0% H₂ and 32.0% O₂. After dilution with room air during spontaneous breathing, the paper estimated inspired fractions of at most 4.08% H₂ and 21.57% O₂.
1,224 mL/min H₂, calculated from the reported total generator flow of 1,800 mL/min × 68.0%.
576 mL/min O₂, calculated from the reported total generator flow of 1,800 mL/min × 32.0%. The actual inspired O₂ fraction was estimated at no more than 21.57% because room air was entrained.
Ambient air delivered at the same total generator flow of 1,800 mL/min through a matched device
Outcomes and reported result
Oxidative-stress and muscle-damage markers, countermovement jump, knee-extensor strength and sprint-cycling performance
Compared with placebo, the H₂/O₂ mixture attenuated the rise in urinary 8-OHdG and the reduction in countermovement-jump height. Other measured performance, blood oxidative-stress and muscle-damage outcomes did not differ.
Gas composition, total flow, calculated component flows, methods, principal results, funding and conflicts checked in the open-access full text; independent appraisal remains incomplete.
A reported association, difference or mechanism is not automatically a clinical benefit.
Limitations and applicability
Very small male-only study. Because the intervention co-delivered O₂, the isolated effect of H₂ cannot be established. Helix Japan funded the study and supplied the gas generator.
Healthy physically active young men during short-term recovery from the study’s strenuous exercise protocol.
No single-study GRADE certainty rating is assigned. Read how records and evidence assessments are prepared.
Sources and record status
PMID: 33380581 · DOI: 10.4103/2045-9912.304222
Open-access full text is available through PMC.
Open-access PMC full text and PubMed bibliographic record. Component flows are transparent calculations from the article’s reported total flow and gas percentages.
10 August 2026
Help people check the facts before they buy.
Hydrogenology keeps 665 source-checked records accessible without advertising or product promotion.
Help us correct the recordReport a discrepancy
Send the exact difference between this page and the linked source. The study reference is attached automatically.